Excavators



Aug. 4, 1964 R. o. BlLLlNGS 3,143,229

EXCAVATORS Filed July 6, 1962 2 Sheets-Sheet 1 INVENTOR. R O. Billings Attorneys g- 4, 1964 R. o. BILLINGS 3,143,229

EXCAVATORS Filed July 6, 1962 2 Sheets-Shee t 2' Attorneys United States Patent 3,143,229 EXCAVATORS Roy 0. Billings, Box 2611, Milwaukee, Wis. Filed July 6, 1962, Ser. No. 267,946 17 Claims. (Cl. 214-147) This invention relates to improvements in excavators, and more particularly to an improved digging bucket and dipstick coupling assembly for an excavator of the type disclosed in my co-pending patent application, Serial No. 159,577, filed December 15, 1961, which application is intended to be incorporated herein by reference.

As is brought out in said prior application, conventional clam-shell type earth excavators are impractical for many digging operations because of their large size, while the smaller, more mobile backhoe type of excavator is unsatisfactory because of its limited digging capacity. For this reason, the principal object of said prior invention was to provide a novel machine combining the versatility and mobility of a backhoe with the greater digging capacity and efliciency of a clamshell excavator.

One of the novel features of said prior invention was the provision of a flexible coupling chain by which the clam-shell type digging bucket is suspended from the lower end of a rigid, pivotal dipstick of the type employed in a backhoe, said flexible connection permitting the application of positive digging force to the bucket through said dipstick, while permitting the dumping of the loaded bucket at various desired angular positions relative to the axis of said dipstick. Unfortunately, however, it has been found that the flexible coupling is a disadvantage when the bucket is being lowered to its digging position, it being diflicult to spot the free-swinging bucket into a narrow trench or small excavation.

With the above consideration in mind, the principal object of the present invention is to provide an excavator of the type having a clam shell digging bucket supported by a rigid, vertically-movable dipstick, as in my prior invention, and which improved structure features a novel bucket and dipstick coupling which is flexible to permit wide angle dumping, but which coupling can be readily adjusted to provide a rigid bucket and dipstick connection during the lowering and spotting operations.

A more specific object of the present invention is to provide an excavator of the type described having a hydraulic ram and sprocket assembly operatively associated with the flexible coupling member in a manner whereby the digging bucket may be drawn upwardly into rigid engagement with the end of the dipstick during the lowering and spotting operation, thus permitting said bucket to be accurately located with respect to the intended digging area.

Further objects of the present invention are to provide a novel digg'uig bucket and dipstick coupling assembly which is simple in design and operation, which is relatively inexpensive in construction, and which is otherwise particularly well adapted for its intended purposes.

With the above and other objects in view, which other objects and advantages will become apparent in the following detailed description, the invention consists of the improved excavator arid all of its parts and combinations as set forth in the specification and claims, and any and all modifications or variations thereof as may come within the spirit of said invention.

In the accompanying drawings, wherein the same reference numerals designate the same parts in all of the views:

FIG. 1 is a fragmentary side elevational view of an excavator unit incorporating the novel bucket and dipstick coupling assembly comprising the present invention, said unit being shown in dot and dash lines in its dumping position;

FIG. 2 is an enlarged, fragmentary side elevational view of the dipstick and digging bucket in their normal, spaced condition, parts thereof being broken away to show the coupling assembly, and a suitable hydraulic system being shown in diagrammatic form; and

FIG. 3 is a view similar to FIG. 2 showing the dipstick and bucket rigidly connected, as during the lowering and spotting operation.

With more particular reference now to FIG. 1 of the drawings, it will be seen that the novel excavator herein concerned includes a turntable 10, which is rotatably mounted on the back of a truck or other vehicle, or which can be part of a trailer-type excavator, there being a boom 11 vertically pivotally mounted on said turntable. Pivotally and longitudinally movably carried by a sleeve bearing 12 on the outer end of said boom is the dipstick 13, and suspended from the lower end of said dipstick by means of a flexible coupling is a digging bucket 20 provided with clam shell type bowl elements 21 having hydraulic opening and closing rams 22. A suitable hydraulic system is provided for said rams, as well as for all of the hydraulically-actuated members hereinafter described, and remote control means for said hydraulic members are conveniently located in the operators cab.

In the use of a novel excavator of the type illustrated, as is described in detail in the aforementioned co-pending application, Serial No. 159,577, the turntable 10 is rotated to swing the boom 11 horizontally over the digging area and said boom is adjusted angularly by means of a hoist line or cable 24. A double-acting hydraulic ram 25 on the underside of the boom is then actuated to swing the sleeve bearing 12 in a vertical plane about its pivot connection to position and lock the dipstick 13 at a desired angle relative to the boom, and said dipstick is urged downwardly through said sleeve, by means of a ram 26 and associated cable 27, to lower the open digging bucket toward the designated point on the ground.

After the bucket 24) is resting on the ground, downward movement of the dipstick 13 is continued until the convex bottom surface of the dipstick foot 14 seats on and bears against radial shoulders 23 formed on the upper surface of said bucket (FIG. 3). When the dipstick is thus positioned against the top of the bucket, the hydraulic bucket rams 22 are actuated to close said bucket, the downward pressure applied by said dipstick causing the bucket clam shell elements 21 to dig deeply into the soil in a pincher or vise action. When sufficient earth has been collected in the bucket the dipstick and boom are hydraulically raised and swung laterally to a position over a dump truck or the like, and the bucket is opened to empty its contents, as is shown in broken lines in FIG. 1. The boom and dipstick are then repositioned and lowered for the next bite or cut, and the operation is repeated.

As is pointed out in the aforementioned co-pending application, with the novel type of excavator described, a positive downward digging force is applied to the clamshell bucket through the rigid dipstick which permits the digging of hard soil in much less time than is possible with conventional excavators of comparable size and power, Moreover, due to the application of such positive digging force, lighter, less expensive materials can be utilized in the construction of the present machine.

Unfortunately, it has been found that the bucket and dipstick coupling disclosed in said co-pending patent application is not entirely satisfactory for its intended purpose. While a flexible coupling is necessary to permit wide angle positioning and dumping, such a coupling arrangement is a disadvantage when the bucket is being lowered to its digging position, it being difficult for the operator to accurately position the free-swinging bucket over the intended digging area. For this reason, the P111!- cipal object of the present invention is toprovide. a novel bucket and dipstick coupling assembly which is flexible under normalconditions, but which can be readily adjusted to provide arigid bucket and dipstick connection during the lowering and spotting operations.

' As'will be seen in FIGS. 2 and 3'of the drawings, in accordance with the present invention the dipstick 13 is I-shaped in cross section, having longitudinal side flanges 13', and the lower end of said I-shaped member iscut away to provide a recess or cutout 19. A pair of general 1y rectangular plates 28 and 29 are welded on opposite sides of the lower end of said dipstick, said'flanges 13 providing spacing therebetween, and spanning said plates and vertically slidably carried in slots 31 therein, is a transverse pin 32 which is projected through the uppermost lirik 160)? 'a flexible coupling chain 15. Said transverse pin 32 is adapted to vertically movably support said coupling chain, as will be hereinafter seen, and said slots 31 are of a length to limit the vertical travel of said pin within predetermined limits. Said uppermost chain link 16 normally hangs downwardly through a central bore 30 in the dipstick foot (FIG. 2), and connected thereto and depending below the dipstick are links 17 and 18, thelatter link'extending through an aperture 33 in the bucket top and being secured to and within the digging bucket by a V transverse pin 34. As in my prior machine, an expansion spring 35 in said bucket body is connected to said lowermost link 18 and is designed to maintain tension on the coupling chain to keep the same taut and to prevent said chain from becoming tangled or fouled during the digging operation; r

Mounted on and between said spaced plates 28 and 29 within the dipstick cutout 19 in the present structure is a vertically-disposed, single-acting hydraulic cylinder 36 having a ram 37 which is extendible downwardly in response' to fluid pressure,as will'be described. A suitable hydraulic system for said ram is shown diagrammatically inFIG. 2 and includes a two-way valve 38, a motor 39, pump 40, and a hydraulic 'fluid reservoir 41.

Rotatably carried on the lower free end of said' ex- 7 tendible ram 37 is a first chain sprocket 42, and rotatably mounted on the plates 28 and 29in a fixed position thereabove is a second chain sprocket 43. A chain 44, hereinafter referred to as the adjustment chain, is anchored to the hydraulic cylinder 36 as at and is trained about said ram sprocket 42 and upwardly'and over' said fixed sprocket 43. The lower end 'of said chain 44 is secured to the aforementioned uppermost coupling link 16, as

shown:

'As illustrated in FIG. 2, when the hydraulic 'ram 37 V is in its normal, retracted condition, that portion of the adjustment chain'44 which extends'upwardly from the link 16, and which is designated by the numeral 44', is of maximum length, thus permitting the vertically-movable coupling chain 15 to assume its lowermost position, and supporting thedigging bucket 20 in spaced relation below the lower end of the dipstick-13. In the latter position, said bucket 20 is free to swing or pivot in any direction, and can be positioned or dumped at any desired angle.

' In accordance with the invention, when the hydraulic ram 37 is extended, asillustrated in FIG. 3, the adjustment chain'44 pulls the coupling chain 15 upwardly intothe dipstick, and the digging bucket 20 is drawn upwardly into engagement with the underside of the dipstick foot, thereby preventing swinging movement of said bucket. In the After the digging bucket 20 in the present invention has been filled, and it is desired to raise and dump the same, the valve 38 between the hydraulic cylinder 36 and the reservoir 41 is opened to permit the return of the fluid to said reservoir. The'weight of the bucket and load causes the ram 37 to be retracted to its normal, non-extended position (FIG. 2), and the bucket again assumes its position spaced below the lower end of the dipstick, and where said bucket may be swung to any desired angular position for discharging.

The wide range of possible angular positions of the bucket relative to the dipstick in the present invention is particularly important when the dirt is being deposited in a dump truck or the like which is spaced from the .excavation, and wherein it is necessary to raise and extend the dipstick as shown in broken lines in FIG. 1. In such instances, the bucket must assume a sharp angular rela tionship to the dipstick axis, and the flexible nature of said coupling is critical. When the proper bucket angle has been obtained, the ram 37 can be partially extended to take up any slack in the coupling chain. Another ad vantage of the flexible bucket coupling incorporated in the present structure is that when said bucket is in its loose condition it can be rotated horizontally to align the same with the particular excavation or intended digging area, and then locked in position, which is important when digging excavation corners or the like.

From the foregoing detailed description, it will be seen that the present invention provides an excavating machine which effectively combines the mobility and versatility of a backhoe with the digging capacity and efliciency of a clam shell excavator, and which machine features an improved dipstick and bucket coupling assembly. With the novel coupling herein disclosed, a flexible connection is normally provided between the dipstick and bucket to obtain maximum operating range and to facilitate dumping, but a rigid connection can be readily obtained between said members through a remotely-controlled hydraulic ram and chain device to ensure the accurate spotting of said digging bucket in a narrow trench or other confined digging area.

With respect to the ram sprocket and chain assembly illustrated and hereinabove described, it is to be understood, of course, that other equivalent mechanisms might also be employed for the same purpose without departing from the spirit of the present invention. It is contemplated, for example, that a cable and sheave mechanism could be used, or any other similar block and tackle type device, or the extendible hydraulic ram could even be connected directly to the coupling chain. Similarly, a cable or other flexible coupling member could be utilized in'lieu of the illustrated chain 15. In short, it is intended that the present invention include not only the embodiment illustrated and hereinabove described, but also any and all modifications or changes therein as may come within the spirit of the invention and within the scope of the following claims.

What I claim is:

1. In an excavator of the type having a dipstick with a digging bucket coupled to the lower end thereof, a bucket and dipstick coupling assembly, comprising: a hydraulic cylinder and ram mounted on and adjacent the lower end of said dipstick, said ram being extendible downwardly along the dipstick; a first wheel rotatably mounted on the lower, 'free end of said ram; a second wheel rotatably mounted on the dipstick in a fixed position above said first wheelga flexible coupling member vertically-movably carried by and normally depending below said dipstick, the lower end of said coupling member being connected to and normally supporting said digging bucket in spaced relation below said dipstick; an adjustment line anchored to said hydraulic cylinder, said adjustment line being trained about said Wheels and being secured to the upper end of said coupling member; and hydraulic means for extending said ram, thereby acting upon said adjustment line and attached coupling memher, to draw said digging bucket upwardly into engagement with the lower end of said dipstick.

2. In an excavator of the type having a dipstick with a digging bucket coupled to the lower end thereof, a bucket and dipstick coupling assembly, comprising: a hydraulic cylinder and ram mounted on and adjacent the lower end of said dipstick, said ram being extendible downwardly along the dipstick; a first chain sprocket rotatably mounted on the lower, free end of said ram; a second chain sprocket rotatably mounted on the dipstick in a fixed position above said first sprocket; a coupling chain vertically-movably carried by and normally depending substantially below said dipstick, said coupling chain having an uppermost link positioned below said second chain sprocket and having a lowermost link connected to and normally supporting said digging bucket in spaced relation below said dipstick; an adjustment chain anchored to said hydraulic cylinder, said adjustment chain being trained about said sprockets and being secured to the uppermost link of said coupling chain; and hydraulic means for extending said ram, thereby acting upon said adjustment chain and the coupling chain attached there-- to, to draw said digging bucket upwardly into engagement with the lower end of said dipstick.

3. In an excavator of the type having a dipstick with a digging bucket coupled to the lower end thereof, a bucket and dipstick coupling assembly, comprising: a hydraulic cylinder and ram mounted on and adjacent the lower end of said dipstick, said ram being extendible downwardly along the dipstick; a first chain sprocket rotatably mounted on the lower, free end of said ram; a second chain sprocket rotatably mounted on the dipstick in a fixed position above said first sprocket; a coupling chain vertically-movably carried by and normally depending substantially below said dipstick, said coupling chain having an uppermost link position below said second chain sprocket and having a lowermost link connected to and normally supporting said digging bucket in spaced relation below said dipstick; an adjustment chain anchored to said hydraulic cylinder, said adjustment chain being trained about said sprockets and being secured to the uppermost link of said coupling chain; hydraulic means for extending said ram, thereby acting upon said adjustment chain and the coupling chain attached thereto, to draw said digging bucket upwardly into engagement with the lower end of said dipstick; and means on said dipstick engageable with said digging bucket when the same is in a raised condition to prevent rotation of said bucket.

4. In an excavator having a pivotally mounted boom projecting outwardly therefrom, a rigid dipstick pivotally connected to an outer portion of said boom, and having a lower end with an interior connector opening, an earth-handling implement having an upwardly facing portion forming a seat for coaction with said lower end of said dipstick, said seat having an opening and there being connector space below and communicating with said opening, a relatively short flexible connector having an upper end connected within said interior opening of the lower end of the dipstick and having a lower end extending through said opening in the seat of the implement and connected within the space below said opening, said flexible connector being of a relatively short length to permit flexible support of the implement in a position suspended only a short distance below the lower end of the dipstick, said flexible connector permitting said lower end of the dipstick to forcibly engage said implement seat when the implement is in engagement with the ground, and separate means for causing upper and lower portions of said flexible connector to enter said connector opening and connector space when the parts are thus engaged so as not to interfere with said engagement, one of said means including a fluid pressure operated cylinder and ram.

5. In an excavator having a pivotally mounted boom projecting outwardly therefrom, a rigid dipstick pivotally connected to an outer portion of said boom, and having a lower convex end with an interior connector opening, an earth-handling implement having an upwardly facing concave portion forming a seat for coaction with said convex lower end of said dipstick, said seat having an opening and there being connector space below and communicating with said opening, a relatively short flexible connector having an upper end connected within said interior opening of the lower end of the dipstick and having a lower end extending through said opening in the seat of the implement and connected within the space below said opening, said flexible connector being of a relatively short length to permit flexible support of the implement in a position suspended only a short distance below the lower end of the dipstick, said flexible connector permitting said convex lower end of the dipstick to forcibly engage said concave implement seat when the implement is in engagement with the ground, and hydraulic means for causing one of the ends of said flexible connector to enter its respective opening when the parts are thus engaged so as not to interfere with said engagement.

6. In an excavator having a pivotally mounted boom projecting outwardly therefrom, a rigid dipstick pivotally connected to an outer portion of said boom, and having a lower end with an interior connector opening, an earthhandling implement having an upwardly facing portion forming a seat for coaction with said lower end of said dipstick, said seat having an opening and there being connector space below and communicating with said opening, a relatively short flexible connector having an upper end connected within said interior opening of the lower end of the dipstick and having a lower end extending through said opening in the seat of the implement and connected within the space below said opening, said flexible connector being of a relatively short length to permit flexible support of the implement in a position suspended only a short distance below the lower end of the dipstick, said flexible connector permitting said lower end of the dipstick to forcibly engage said implement seat when the implement is in engagement with the ground, and means including a spring connected to one of said portions, and a fluid pressure operated ram connected to the other of said portions for causing upper and lower portions of said flexible connector to enter said connector opening and connector space when the parts are thus engaged so as not to interfere with said engagement.

7. In an excavator having a pivotally mounted boom projecting outwardly therefrom, a rigid dipstick pivotally connected to an outer portion of said boom, and having a lower end with an interior chain opening, an earth-handling implement having an upwardly facing portion forming a seat for coaction with said lower end of said dipstick, said seat having an opening and there being chain space below and communicating with said opening, a chain having elongated links and having an upper link slidably connected within said chain opening of the lower end of the dipstick and having a lower link extending through said opening in the seat of the implement and slidably connected within the chain space below said opening, said chain comprising only a few links to permit flexible support of the implement in a position suspended only a short distance below the lower end of the dipstick, said chain permitting said lower end of the dipstick to forcibly engage said implement seat when the implement is in engagement with the ground, and separate means for causing upper and lower portions of said chain to enter said chain opening and chain space when the parts are thus engaged so as not to interfere with said engagement, one of said means including a fluid pressure operated cylinder and ram.

8. In an excavator having a pivotally mounted boom projecting outwardly therefrom, a rigid dipstick pivotally connected to an outer portion of said boom, and having a lower end with an interior chain opening, an earth-handling implement having an upwardly facing portion forming a seat for coaction with said lower end of said dipstick, said seat having an opening and there being chain space below and communicating with said opening, a chain having elongated links and having an upper link slidably connected within said chain opening of the lower end of the dipstick and having a lower link extending through said opening in the seat of the implement and slidably connected within the chain space below said opening, said chain comprising only a few links to permit flexible support of the implement in a position suspended only a short distance below the lower end of the dipstick, said chain permitting said lower end of the dipstick to forcibly engage said implement seat when the implement is in engagement wtih the ground, and means including a fluid pressure operated ram connected to at least one of said chain portions for taking up slack in the chain when the parts are thus engaged so as not to interfere with said engagement.

9. In an excavator having a pivotally mounted boom projecting outwardly therefrom, a rigid dipstick pivotally connected to an outer portion of said boom, and having a lower end with an interior chain opening, a pin extending across said chainopening, an earth-handling implement having an upwardly facing portion forming a seat for coaction with said lower end of said dipstick, said seat having an opening and there being chain space below and communicating with said opening, a pin extending across said chain space, a chain having elongated links and having an upper link slidably connected by means of said pin within said chain opening of the lower end of the dipstick and having a lower link extending through said opening in the seat of the implement and slidably connected by means of said pin'within the chain space below said opening, said chain comprising only a few links to permit flexible support of the implement in a position suspended only a short distance below the lower end of the dipstick, said chain permitting said lower end of the dipstick to forcibly engage said implement seat when the implement is in engagement with the ground, and means including a fluid pressure operated ram for causing upper portions of said chain to enter said chain opening when the parts are thus engaged so as not to interfere with said engagement.

10. In an excavator having a pivotally mounted boom projecting outwardly therefrom, a rigid dipstick pivotally connected to an outer portion of said boom, and having a lower end with an interior chain opening, a pin extending across said chain opening, an earth-handling implement having an upwardly facing portion forming a seat forcoaction With said lower end of said dipstick, said seat having an opening and there being chain space below and communicating with said opening, a pin extending across said chain space, a chain having elongated links and having an upper link slidably connected by means of said pin within said chain opening of the lower end of the dipstick and having a lower link extending throughsaid opening in the seat of the implement and slidably connected by means of said pin within the chain space below said opening, said chain comprising only a few links to permit flexible support of the implement in a positionsuspended only a short distance below the lower end of the dipstick, said chain permitting said lower end of the dipstick to forcibly engage said implement seat when the implement is in engagement with the ground, means including a fluid pressure operated ram for causing upper portions of said chain to enter said chain opening when the parts are thus engaged so as not to interfere with said engagement, and other means for causing the lower portion of said chain to enter said chain space when the parts are thus engaged.

11; In an excavator of the type having a dipstick with a digging bucket coupled to the lower end thereof, a bucket and dipstick coupling assembly comprising: an hydraulic cylinder and ram mounted on and adjacent the lowerend of said dipstick and extendable in a direction parallel to the longitudinal axis of the dipstick, a flexible coupling member vertically movably carried by and normally depending below said dipstick, the lower end of said coupling member being connected to and normally supporting said digging bucket in spaced relation below said dipstick, and means including an-adjustment line connected to said hydraulic cylinder and to the upper end of said coupling member for controlling the slack in said coupling member whereby the digging bucketmay be drawn upwardly into engagement with the lower end of the dipstick upon operation of said hydraulic cylinder and ram. 7 7

12. In an excavator having a pivotally mounted boom projecting outwardly therefrom, a rigid dipstick pivotally connected to an outer portion of said boom, and having a lower end with an interior chain opening, a tool having an upwardly facing portion forming a seat for coaction with said lower end of said dipstick, a chain having elongated links and having an upper link slidably connected within said chain opening of the lower end of the dipstick and having atlower link connected to the tool, said chain comprising only a few links to permit flexible support of the tool in a position suspended only a short distance below the lower end of the dipstick, said chain permitting said lower end of the dipstick to forcibly engage said tool seat when the'tool is-in engagement with the ground, and meansincluding a fluid pressure operated ram at the lower end of the dipstick connected to said upper link for taking up slack in the chain when the parts are thus engaged so as not to interfere with said engagement, and for drawing the tool into rigid engagement with the lower end of the dipstick.

13. In an excavator having a pivotally mounted boom projecting outwardly therefrom, a rigid'dipstick pivotally connected to an outer portion of said boom, and having a lower end with an interior chain opening, a pin extending across'said chain opening, a tool having an upwardly facing portion forming a seat for coaction with said lower end of said dipstick, a pin on said tool, a chain having elongated links and having an upper link slidably connected by means of said pin within said chain opening of the lower end of the dipstick and having a lower link connected by means of said pin to the tool, said chain comprising only a few links to permit flexible support of the implement in a position suspended only a short distance below the lower end of the dipstick, said chain permitting said lower end of the dipstick to forcibly engage said implement seat when the implement is in engagement with the ground, and means including a fluid pressure operated ram for causing upper portions of said chain to enter said chain opening when the parts are thus engaged so as not to interfere with said engagement, and for drawing the tool into rigid engagement with the lower end of the dipstick.

14. In an excavator having a pivotally mounted boom projecting outwardly therefrom, a rigid dipstick pivotally connected to an outer portion of said boom, and having a lower end with an interior chain opening, a pin vertically slidably extending across said chain opening, a tool having an upwardly facing portion forming a seat for coaction with said lower end of said dipstick, a pin on said tool, a chain having elongated links and having an upper link slidably connected by means of said pin within said chain opening of the lower end of the dipstick and having a lower link connected by means of said pin to the tool, said chain comprising only a few links to permit flexible support of the implement in a position suspended only a short distance below the lower end of the dipstick, said chain permitting said lower end of the dipstick to forcibly engage said implement seat when the implement is in engagement with the ground, and means including a fluid pressure operated ram for causing upper portions of said chain to enter said chain opening when the parts are thus engaged so as not to interfere with said engagement, and for drawing the tool into rigid engagement with the lower end of the dipstick.

15. In an excavator of the type having a dipstick with a tool coupled to the lower end thereof, a bucket and tool coupling assembly comprising: an hydraulic cylinder and ram mounted on and adjacent the lower end of said dipstick and extendable in a direction parallel to the longitudinal axis of the dipstick, a flexible coupling member vertically movably carried by and normally depending below said dipstick, the lower end of said coupling member being connected to and normally supporting said tool in spaced relation below said dipstick, and means including an adjustment line connected to said hydraulic cylinder and to the upper end of said coupling member for controlling the slack in said coupling member whereby the digging bucket may be drawn upwardly into engagement with the lower end of the dipstick upon operation of said hydraulic cylinder and ram.

16. In an excavator having a pivotally mounted boom projecting outwardly therefrom, a rigid dipstick pivotally connected to an outer portion of said boom and having a lower end with an interior chain opening, a pin extending across said chain opening and supported for vertical movement, a tool having an upwardly facing portion forming a seat for coaction with said lower end of said dipstick, means on said tool extending through a lower link of said chain, and means including a fluid pressure operated ram in said chain opening at the lower end of 1% the dipstick connected to an upper link of said chain for taking up slack and drawing the tool into rigid engagement with the lower end of the dipstick, said chain com prising only a few links to permit flexible support of the implement in a position suspended only a short distance below the lower end of the dipstick.

17. In an excavator having a pivotally mounted boom projecting outwardly therefrom, a rigid dipstick pivotally connected to an outer portion of said boom and having a lower end with an interior chain opening and with circumferentially spaced projections, a tool having an upwardly facing portion forming a seat for coaction with the lower end of said dipstick, said seat having circumferentially spaced projections, a chain having elongated links and having a lower link connected to said tool centrally of said seat, and means within said chain opening at the lower end of the dipstick for drawing the tool into rigid engagement with the lower end of the dipstick with the projections on the lower end of the dipstick interengaging with the projections on the tool seat, said chain comprising only a few links to permit flexible support of the tool in a position suspended only a short distance below the lower end of the dipstick.

Prayer Aug. 6, 1911 McLean Jan. 22, 1957 

1. IN AN EXCAVATOR OF THE TYPE HAVING A DIPSTICK WITH A DIGGING BUCKET COUPLED TO THE LOWER END THEREOF, A BUCKET AND DIPSTICK COUPLING ASSEMBLY, COMPRISING: A HYDRAULIC CYLINDER AND RAM MOUNTED ON AND ADJACENT THE LOWER END OF SAID DIPSTICK, SAID RAM BEING EXTENDIBLE DOWNWARDLY ALONG THE DIPSTICK; A FIRST WHEEL ROTATABLY MOUNTED ON THE LOWER, FREE END OF SAID RAM; A SECOND WHEEL ROTATABLY MOUNTED ON THE DIPSTICK IN A FIXED POSITION ABOVE SAID FIRST WHEEL; A FLEXIBLE COUPLING MEMBER VERTICALLY-MOVABLY CARRIED BY AND NORMALLY DEPENDING BELOW SAID DIPSTICK, THE LOWER END OF SAID COUPLING MEMBER BEING CONNECTED TO AND NORMALLY SUPPORTING SAID DIGGING BUCKET IN SPACED RELATION BELOW SAID DIPSTICK; AN ADJUSTMENT LINE ANCHORED TO SAID HYDRAULIC CYLINDER, SAID ADJUSTMENT LINE BEING TRAINED ABOUT SAID WHEELS AND BEING SECURED TO THE UPPER END OF SAID COUPLING MEMBER; AND HYDRAULIC MEANS FOR EXTENDING SAID RAM, THEREBY ACTING UPON SAID ADJUSTMENT LINE AND ATTACHED COUPLING MEMBER, TO DRAW SAID DIGGING BUCKET UPWARDLY INTO ENGAGEMENT WITH THE LOWER END OF SAID DIPSTICK. 